Researchers have recently uncovered a new bacterium that compromises the immune system in the gut, potentially playing a role in various inflammatory and infectious gut ailments. This team has pinpointed the bacterium, Tomasiella immunophila (or T. immunophila), which significantly disrupts an essential immune element of the gut’s complex protective immune barrier.
Cleveland Clinic researchers have made a significant discovery of a new bacterium that weakens the immune defenses in the gut, which may lead to specific inflammatory and infectious gut diseases.
The team has identified this bacterium, Tomasiella immunophila (T. immunophila), which is crucial for breaking down an important immune component in the gut’s intricate protective mechanism.
Recognizing this bacterium marks an initial step towards creating novel treatments for a range of inflammatory and infectious gut diseases. These diseases, which include inflammatory bowel disease, Crohn’s disease, and ulcerative colitis, are linked to lower levels of secretory immunoglobulin A (SIgA), an antibody that safeguards mucosal surfaces.
This research, featured in the journal Science, was spearheaded by Thaddeus Stappenbeck, M.D., Ph.D., chair of the Cleveland Clinic’s Department of Inflammation and Immunity, along with Qiuhe Lu, Ph.D., who served as the first author.
“Our research highlights the essential role of a specific element within the gut microbiome in affecting human health and disease,” remarked Dr. Stappenbeck. “By identifying this bacterium, we’ve deepened our understanding of gut diseases and unveiled a promising new potential for treatment. Identifying the cause behind the weakening of the gut’s protective adaptive immune barrier is a notable advancement towards developing much-needed therapies for conditions such as inflammatory bowel disease, Crohn’s disease, and ulcerative colitis.”
In the gut, SIgA continuously binds to microbes, preventing them from invading and harming the body’s tissues. Earlier studies by the team indicated that certain gut bacteria might lower SIgA levels, increasing susceptibility to infections and escalating inflammation.
In this latest research, scientists observed that the presence of T. immunophila in the gut heightens vulnerability to pathogens and slows the repair process of the gut’s protective barrier. The name T. immunophila pays tribute to a trailblazer in the field of immunology; SIgA was first identified by Dr. Thomas Tomasi, who published his groundbreaking findings in the journal Science in 1963.
“The thorough and insightful study led by Drs. Stappenbeck and Lu reveals an exciting possible reason why some individuals have low or non-existent levels of SIgA in their gut while still maintaining normal levels in their bloodstream,” said Michael Silverman, M.D., Ph.D., a specialist in the Division of Infectious Diseases at Children’s Hospital of Philadelphia.
Dr. Silverman, who has expertise in immune system development, contributed insights on the research findings. “This discovery is crucial since SIgA in the intestines acts as a vital part of the defense against the trillions of microorganisms residing in our intestines,” he explained. “This research offers a new pathway for developing treatments aimed at regulating SIgA in the gut to enhance health.”
“It’s known that many patients experience this deficiency, which puts them at risk for infections and inflammation in the intestine,” stated Dr. Lu. “We suspected that a gut microbe capable of degrading SIgA was responsible. We believe that our findings can unveil significant therapeutic targets for various inflammatory and infectious diseases in humans.”
